Overhead or gantry crane with a yoke carrying electromagnets

ABSTRACT

Overhead or gantry cranes have generally a crab or trolley from which the yoke is suspended. Instead of the crab which cannot bring the yoke all out to the legs of the crane now a yoke is applied carried by four rope parts from independently operated pulleys at each of the four crane corners.

United States Patent [1 1 Madsen [4 1 Sept. 3, 1974 OVERHEAD OR GANTRY CRANE WITH A YOKE CARRYING ELECTROMAGNETS [75] Inventor: Eigil Madsen, Svestrup Pr. Olstykke,

- Denmark [73] Assignee: H. Nielsen 8: Son M askinfabrik A/S, Herlev, Denmark [22] Filed: May 21, 1973 [21] Appl. N0.: 362,554

. Related U.S. Application Data [62] Division of Ser. No. 138,706, April 29, 1970.

[52] U.S. Cl 212/14, 212/77, 294/67 R, 294/81 R [51] Int. Cl. B66c 17/04 [58] Fie ld 0f S earch. ..294/67 R, 67 B, 67 D, 67 DA, 294/81 R, 81 SF; 214/14 R, 15 R; 212/10,

[56] References Cited UNITED STATES PATENTS 3,656,795 4/1972 White et a1. 294/67 R Primary ExaminerEv0n C. Blunk Assistant Examiner-James L. Rowland Attorney, Agent, or FirmBrowne, Beveridge, DeGrandi & Kline [57 ABSTRACT Overhead or gantry cranes have generally a crab or trolley from which the yoke is suspended. Instead of the crab which cannot bring the yokeall out to the legs of the crane now a yoke is applied carried by four rope parts from independently. operated pulleys at each of the four crane comers.

5 Claims, 4 Drawing Figures Pmmmsw 3 w sum 20: 2

This is a division, of application Ser. No. 138,706,

filed Apr. 29, 1970.

This invention relates to an overhead or gantry crane which moves on two parallel rails and has a yoke carrying electromagnets.

Generally such cranes have a crab or trolley which .moves on the crane bridge or girder and from which the yoke is suspended.

The present invention is concerned with a crane without crab, but with parts carrying the yoke and making it possible to pass the yoke fully out to the legs of the crane, which is impossible with the use of a crab because the length of same is many times in excess of the width of the yoke.

According to the invention the yoke is carried by four rope parts, two at or near each end up around the rope pulleys, each provided in its separate corner of the travelling parts of the crane and each wound on its separate, preferably independent operated rope drum. By hauling and veering the said four rope parts in suitable manner, the yoke may be passed over the whole area between the legs of the crane and/or its vertical supporting wall, and the rope parts may be fastened at the ends of the yoke, by which an efficient angular guiding of the yoke during transport and hoisting is obtained. It is furthermore possible to turn the yoke to a considerable extent and also pitch it.

According to the invention each rope part may be doubled by means of a rope part passed to the center of the yoke. The said rope part relieves the correspond ing outer rope part without preventing the said turning and pitching.

According to the invention the rope drums in either side of the crane may be coupled together, which gives a very simple operation of the said drums and is of importance if hydraulic motors are used.

On the other hand, in such cases it is not possible to turn or pitch the yoke, and it is also difficult to introduce correction for any occurring extensions of the individual rope parts. In this case it is advantageous according to the invention to attach the rope parts passed to the ends of the yoke to laterally movable means provided on the yoke. By moving the said means laterally to opposite sides in relation to each other the yoke may be aligned if it receives an undesired turning, and the yoke may also be turned within certain limits to suit requirements. I

The laterally movable means may according to the invention be pivotal about pivots which are parallel with the longitudinal axis of the yoke, and this provides a very simple design of the said means.

However, according to the invention the laterally movable means may alsobe supported in cross slides or cross carriages near the ends of the yoke, which permits of a very robust construction so that this embodiment may be chosen for yokes that have to carry very heavy loads.

According to the invention the cross slide or cross carriage may have attachment means for the rope parts, adjustable for'height. This provides the possibility of correcting any undesired pitching of the yoke, but may further be utilized in case there is a special desire to work with a pitched yoke.

Finally, the laterally movable means may according to the invention be moved synchronously by means of a power-operated cable laid around cable pulleys at or directly outside each of the upper corners of the yoke.

Since it is possible to use a common cable which is passed along the upper side of the yoke it is sufficient.

to transmit the operating power to both of the laterally movable means by a single source of power, for example a hydraulic cylinder which is mounted on the central part of the yoke.

The drawing shows a couple of embodiments of the crane according to the invention.

FIG. 1 is a side elevation of the crane,

FIG. 2 is a top view of same,

FIG. 3 a modified embodiment of the yoke of the crane, viewed in perspective on a larger scale, and

FIG. 4 a part of a further embodiment of the crane yoke.

Referring to the drawing, 1 and 2 are columns carrying rails 3 on which an overhead girder 4 may travel.

The yoke 5 of the crane is suspended by means of four ropes 6, 7, 8 and 9 each passed over its separate rope pulley 10, 11, 12 and 13 arranged in the corners of the girder 4 and hence passed each to its separate drumQThe shafts of the drums are coupled together in pairs, and the drums l4 and 17 are driven by a hydraulic motor 18, whereas the two other drums are driven by a hydraulic motor 19. I

In FIG. 2 the yoke 5 is suspended approximately midway beneaththe crane, whereas in FIG. 1 the yoke is pulled almost intoposition very close to the column 1. The vertical as well as the horizontal movements of the yoke are determined by operation and regulation of the motors l8 and 19. Each of the aforesaid rope parts may be doubled by a rope part 20, 21, 22 and 23 ,passedto, the central part of the yoke 5 for relieving the original rope parts.

24 is an operating cabin attached to the girder 4.

The yoke 5 is turned by means of a mechanism (FIG. 3) which displaces the connecting points 26 and 27 of the rope parts in lateral direction, whereas the third and central connecting point 28 remains in its position.

The connectingv points 26 and 27 are located at the upper end of a pair of arms 29 and 30 which are pivotable about longitudinal pivots 31 provided on the yoke 5. The said arms may be swung out into opposite positions in relation to each other by means of a cable 32 which at each end of the yoke is passed over cable pulleys 33 mounted on brackets 34 and inside small cable pulleys 35 mounted on the upper side-of the yoke. Both ends of the cable 32 are passed to a hydraulic cylinder 36 on the central part of the yoke. By means of the said cylinder the cable ,may be moved to and fro so as to turn the arms 29 and 30, the cable being passed through and attached to ears '3-7 of each arm.

FIG. 4 shows a similar mechanism, the pivotable arms 29. and 30 being only substituted by small carriages 38 provided at either end and capable of travelling in a transverse guideway 39. The carriages carries an upright 40 with a slit 41 to which the attachment 42 for the rope parts may be fastened at any desired level. This provides possibility of adjusting the pitching movement of the yoke.

I claim:

1. In an overhead or gantry crane, including girder means which moves on two parallel rails, a load carrying yoke suspended in position under the crane by four rope parts attached in pairs to two support points, one for each end of said yoke in which each of said two support points is attached to said yoke by laterally movable support means attached to said yoke, said laterally movable means being moved synchronously by a power-operated cable laid around cable pulleys at or directly outside the corners of the yoke.

2. A crane as in claim 1, said laterally movable support means being a pair of supporting members for said ends of the yoke to displace the yoke ends oppositely for orienting the yoke in respect to the girder means.

I being adjustable for height. 

1. In an overhead or gantry crane, including girder means which moves on two parallel rails, a load carrying yoke suspended in position under the crane by four rope parts attached in pairs to two support points, one for each end of said yoke in which each of said two support points is attached to said yoke by laterally movable support means attached to said yoke, said laterally movable means being moved synchronously by a power-operated cable laid around cable pulleys at or directly outside the corners of the yoke.
 2. A crane as in claim 1, said laterally movable support means being a pair of supporting members for said ends of the yoke to displace the yoke ends oppositely for orienting the yoke in respect to the girder means.
 3. A crane as claimed in claim 1 characterized in thAt the laterally movable means are pivotal about pivots which are parallel with the longitudinal axis of the yoke.
 4. A crane as claimed in claim 1 characterized in that the laterally movable means are supported in cross slides or cross carriages near the ends of the yoke.
 5. A crane as claimed in claim 4, characterized in that the cross slide or the carriage carries attachment means for the rope parts, the said attachment means being adjustable for height. 